


breathe with me

by LyraLV



Category: Undertale (Video Game)
Genre: Fingerfucking, M/M, Multiple Orgasms, Overstimulation, Praise Kink, Underfell Sans (Undertale), background edgepuff, kustard - Freeform
Language: English
Status: Completed
Published: 2019-08-13
Updated: 2019-08-13
Packaged: 2020-08-23 21:55:03
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 8,156
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20235946
Author URL: https://archiveofourown.org/users/LyraLV/pseuds/LyraLV
Summary: Sans spends an afternoon discovering a new tier in his relationship with Red.





	breathe with me

**Author's Note:**

> Content warning in the endnotes, but the majority of this is rather light!

Most Friday afternoons are spent in an artfully lazy way for Sans. Due to his flexible schedule and ability to act as his own boss, he can choose what day (or days) of the week he wants off. Freelance work has been something of a gift and a curse for him. He can pick his own hours, but he also has to commit to those hours or else he’ll get zero work done. 

More often than not, Sans struggles with keeping to his own schedule. It’s the temptation of sprawling on the living room couch and continuing the sleep he’d left behind in his bedroom. There’s no question that Sans will get his work done at some point, but he typically ends up saving it for the very last minute. Procrastination breeds perfection, right? Sans puts out his best work when he’s under pressure (and he’s been under a lot of it lately.)

In any case, Fridays are always Sans’s guaranteed lazy day. His morning doesn’t start until at least ten a.m., and even that’s being a little generous. It would probably start hours later if he had the house to himself. As such, his daily routine finds him in the bathroom one Friday afternoon, sleepily staring into the mirror as he holds a toothbrush against his teeth, moving his arm the bare minimum as he lets the toothbrush hum against his teeth and do most of the work for him. God, whoever invented electric toothbrushes was a genius. It’s advocated for Sans’s listlessness in more ways than one. Sans is just happy to enjoy the quiet of an easy afternoon with no responsibilities planned for the day. It’s peaceful.

“Hey,” a voice calls from down the hallway, “If you’re getting off right now, you might not want to leave the door wide fucking open.”

Sans exhales, causing toothpaste and spittle to spray onto the mirror. He stares at it with a tiny bit of resentment. Just like that, the serenity of Sans’s day drifts away to make room for the new addition of Sans’s unwarranted roommate. The voice is exhibit A for why stress has wriggled back into his life. Were Sans any less moral, he might have just kicked said owner of voice out into another home. Far, far away from here. Anywhere but here honestly. 

Unfortunately, Sans is what monsters assume is a nice guy, and his nagging conscience wouldn’t allow him to not give homeless monsters like Red and Edge someplace to live until they can get back on their feet. 

Sans has been there before. Struggling to survive when he only had Papyrus. 

So, Red and Edge have moved in with them temporarily. It’s fortunate there was an unoccupied guest bedroom in Sans and Papyrus’s house. Ever since Red and Edge “hacked the system” and got Sans’s seemingly broken machine to spit them out into his lab, looking haggard and desperate, like scarred animals backed into a corner, they’ve worked their way past his defenses and into his soul. He cares about them. 

Originally, Red and Edge were planning to move into a house of their own. That was before Sans found out about Edge and Papyrus. Now, it looks like Red might remain Sans’s sole roommate as Paps and Edge move out together if things continue to progress the way they are. It’s ok. Sans is fine with it. He’ll deal with the gaping hole of Paps’s absence like he’s dealt with everything else—just sweep it under the rug and roll with the bad days as they come. Sans is an adult, and he’s happy for his brother.

“Oh, you’re brushing your teeth. Totally not what I thought you were doing.”

Sans turns off the toothbrush, spits into the sink, rinses out his mouth, and then lifts his head to raise a brow at the invader standing in the bathroom doorway.

“What exactly did you think I was doing?”

Red grins. It’s unfair that Sans find it in any way attractive because Red is essentially himself. 

(Sans internally berates himself for that thought because no, they are not the same. Only one of them has some idea of decency, and it isn’t Red.)

“Y’know.” Red shrugs like Sans should know. Unfortunately, Sans does, and he hates that he can see where this is going. “Maybe a little feel good for the day. Embracing some love between the thighs. Getting a little jazzy with those good vibes—”

“Thank you. You’ve said enough.”

“Don’t think I have.” Red waggles his brows. “Feeling a little, heh, bonely? The bed too cold at night? Because if you’re looking for a little loving—”

“What?” Sans grins ruefully. “You’ll offer me some sacrificial warmth?”

Red holds up a hand. “Hey, scouts honor. I never leave ‘em high and dry.” Red looks him up and down with a half-lidded stare that spreads a slow warmth through Sans’s bones. “You seem to be looking to get a little wet.”

“Should’ve caught me when I was in the shower, then.”

Red perks up with sudden interest as if he’s laid eyes on some tasty information in that one statement. 

“You offering?” he asks. “‘Cause there ain’t no rules to say you can’t get clean twice.”

Sans looks away from that predatory stare. The conversation feels like it’s somehow slipped out of his control in a matter of seconds and is spiraling with increasing potential towards something he’s afraid to name for fear that he might not find it as distasteful as he should. Instead, he looks at the faucet with the intensity of one trying to see all the invisible bacteria growing around it. He wonders if that’s what his brother sees every time he so much as looks at anything in their house.

“Uh,” he says intelligently, “That’s not really on my to-do list, no. Considering the fact that you’ve never so much as suggested any interest in sharing some water.”

“Or maybe you’ve just been missing all the signs because holy fuck, you are blind.”

Sans looks at him. Red stares back.

“What?”

Red shrugs. “I mean, there really hasn’t been any subtlety here, sweetheart. Last week, I received a copy of the _Kama Sutra_ from your bro. Not that I didn’t already have my own copy, but the boss was happy to not have to share with me anymore. So, the book didn’t go to waste.”

The headache forming in Sans’s temples increases the more Red talks. He rubs it away and holds up a hand in the universal gesture for stop. Or maybe he’s asking for mercy. He could have gone his entire life without ever knowing Papyrus was invested in Red’s sex life (and wasn’t that just a horrifying thought in itself), and he would have been happily, blissfully ignorant. 

Red has a habit of unloading secrets on Sans that he wished he’d never learned. Like the time Red told him Edge and Papyrus were fucking. Sans had nearly pulled a blaster on him because he thought it‘d been intended as a threat. But no, as it turned out, Red was just oversharing (_again_), and he was looking for someone with whom he could share his frankly terrifying and inappropriate glee that his brother had gotten laid. Sans had almost laid _Red_ out for it, but then he’d received a mysteriously well-timed text from Papyrus saying not to wait up because he and Edge were getting dinner at some fancy restaurant. The text had been followed by a photo of them, Papyrus looking happier than Sans had seen him in months and Edge with his usual morose composure, though his amusement and fondness was clear in the glint of his eyelights and the hand that was intertwined with Papyrus’s, and— 

Well.

Sans can set aside his protective anger for the sake of his brother’s happiness. That doesn’t mean that after receiving the text he didn’t immediately leave Red on the living room couch and go into the bathroom to dunk his head under the faucet and try to rinse out any and all thoughts of his brother having sex.

(He’d seen the intense look in Red’s bright eyes when he’d used gravity magic to throw him against the couch, his limbs sprawled against the cushions. Sans had thought it was rage, but maybe, now that he thinks about it, it might have been something else.)

Regardless, Sans is glad that Papyrus has found someone. Particularly Edge, because for all of his LV and EXP and silent judgment, Edge is a good dude. He’s good for Papyrus in ways that Sans can’t and never wants to be. It’s good that Paps has found something substantial in his life. 

The problem seems to be that Papyrus has noticed the lack of sexual substance in Sans’s and has now apparently confided in Red to provide that missing aspect. A tiny part of Sans is bitter that his brother went behind his back like this, but it’s quickly quashed with the reminder that it’s just another way of Papyrus showing he cares.

(Sans just wished this was one part of his life that had remained dormant.)

With the way Red is looking at him now, that old, forgotten curl of heat and longing is beginning to stir, and it’s sending unfortunate signals that make his bones feel slightly overheated. He can only hope Red hasn’t noticed.

(He’s definitely noticed.)

Sans swallows and shrugs, all nonchalant. The definition of Mr. Cool. He says, “I dunno. It’s not like you ever said anything, and I haven’t really thought about it.”

Red lifts a brow.

“Sweetheart, I left a sticky note on your pillow that said, “This piece of paper isn’t the only thing that could be sticky in your bed.””

Sans shrugs again, but he thinks his face might be a little hot. “Thought that was Edge criticizing my unwashed sheets.”

Red rolls his eyelights. “No, you didn’t. You and me've got the same handwriting. I’m telling you you’re encased in a vial of denial, and I’m here to smash it.” His grin looks fitting for a shark.

“Sounds unsanitary,” Sans says as he feels a drop of sweat run down the back of his skull.

“Oh, it’s plenty dirty.” Red’s low voice is doing things to Sans that he’d rather not define. “I’m down to get you all sorts of messy and messed up. We’re gonna have a real fun time experimenting. But,” he holds up his hands in a shrug, “that’s only if you’re willing. And interested.” 

He drops his hands, takes a pointed step back, and eyes Sans up and down again. 

“Maybe just willing. You look like you’re already collecting interest, heh.”

Sans gives him a deadpan look. “Yeah, I’m just waiting for you to take out a loan, I’m so bored.”

“I’m sure you are babe. ‘S why I’m offering.” The glint in Red’s eyes spell trouble. “And I always pay back my interest.”

This is getting out of hand. Sans can’t really fault Red either because the more the asshole opens his mouth, the more Sans finds his gaze drawn to it. Sans feels like a fish watching a piece of bait dangle in front of him, and he’s about to take a bite. Trouble with baited hooks is that they bite back twice as hard.

Sans isn’t so sure he’d be opposed to that.

As the silence draws out, Red says, “Hey, man, if you don’t want to make whoopee, then that’s fine. We can drop it if you don’t feel like fooling around. No pressure.”

Red is as good as his word. Sans knows that. It likely comes from Red’s history of stressing consent, and that thought releases some of the tension from Sans’s shoulders. At the very least, he knows Red’s serious about this.

A little afternoon delight. No gimmicks, no hassle. Just some good old fashioned fucking each other through the mattress.

Yeah. Sans wants this. It’s just hard admitting as much.

He tries for casual and says, “Not really looking to get back in the shower again. Too much effort, y’know?” He chances a look at Red with a half-assed grin. 

Red drops back on his heels from where he’d been leaning forward. (Sans hadn’t even seen him inching closer.) He looks surprisingly (refreshingly) unvexed as he shrugs.

“No prob,” he says. “Just was curious if you wanted to get a little wet ‘n wild.”

Red turns to leave, and Sans’s soul lurches along with the unconscious step forward he takes.

Fuck.

“I’m not saying I’m not interested.” He stammers out as Red pauses and looks back at him. “Just—”

Shit, this shouldn’t be as difficult as it is. He tries again. 

“Look, I’m curious, too, and if you’d like to— I mean, we could. If you want.” Very intelligible. Sans can handle chatting with a kid who once held a knife to his chest, but he gets a little tongue-twisted at the thought of some simple, free fucking. Maybe he’s just not used to getting loose for fun when there was always a little more gold in his wallet after he left his fuck for the night. Sometimes, there was more than one. He’s always just gotten by and never close to anyone. Choosing to do this with Red could screw things up if he’s not careful. It could make him open and susceptible. 

But he knows it wouldn’t be like that. Not with Red, despite how much of a grade A dickbag he is. Maybe it’s been too long. Maybe Sans needs this. (He already knows what his body wants.) And the realization that he could have something for himself for once is tantalizing in a way that he hasn’t felt in years. Sans’s soul flutters in tune with his breath. He doesn’t think he imagines the way Red’s eyelights flare or the way his grin widens as he reclaims his steps towards Sans.

Red assesses Sans with a long searching look, trying to find any sign of uncertainty or discomfort on Sans’s face. Sans is a little uncertain of how to approach things, but the idea of fooling around with Red is quickly turning into a possible tangibility, and the thought shoots warmth straight through his soul. Red stares at him like he can see the anticipation and grins.

“Yeah?” He asks. 

Sans nods. Probably best if he doesn’t try to say anything for the moment.

Another long moment of searching, Sans distinctly aware of his elevated breathing, and they haven’t even done anything, for fuck’s sake. Maybe he should have listened when Grillby told him he was looking too uptight lately and needed to release some of that tension.

(He tries not to think about how that felt like an invitation, too. He’s just been a little keyed up, damnit.)

Red stares at him like he’s been stranded on an island for weeks, and Sans is the first boat he’s seeing on the horizon. His eyelights drag down Sans’s body like a touch, viewing him with new appreciation. Or maybe the appreciation’s always been there. Sans is pretty good at letting obliviousness crowd his vision.

Whatever Red is looking for he seems to find as a certain excitement burns in his gaze. He takes a noticeable step closer. Sans feels like his senses have suddenly woken up from whatever listless state he was previously in. He’s distracted by Red’s nearness.

“You really in for this?” Red double checks. Sans nods again, but Red shakes his head. “Talk to me, darling.”

The pet name is absolutely ridiculous, and Sans’s body is equally so for shuddering in response to it.

“Yeah. I’m in. Why don’t we let loose some. Really get our gears grinding.”

Red steps into his space, gently using his weight to push Sans against the counter, the granite digging into his pelvis. Sans’s hands reach forward of their own volition, slotting along Red’s rib cage, fingering the the shape of his bones indented in his shirt. Red’s eyes burn bright. His stare makes Sans want to step out of sight, away from the intensity of his gaze, like he’s being seen to his core. As if reading his thoughts, Red smirks and palms the sides of Sans’s pelvis, fingers slipping underneath the shirt as his thumbs smooth against the iliac crests. Sans is acutely aware of the touch that sends searing heat between his legs.

Red’s eyes flit down from Sans’s own and focus on his mouth. 

“Yeah,” he breathes. “Think I will.”

Sans helps him close the distance between them, and Red licks at his teeth until Sans parts them and lets Red’s tongue slips inside, tasting him. The groan shudders out of Sans without his consent, and he grips Red’s shoulders in an attempt to pull him impossibly closer and deepen the kiss. His desire results in the sharp edge of teeth gently pricking his tongue like a warning, and Sans shivers. The noise that escapes him is dwarfed by Red’s own enthusiastic groan.

Red gently knees Sans’s legs open a touch wider and slots his thigh between Sans’s. The closeness is addictive, a sensation that Sans’s body has long been deprived of, but as Red pushes even closer still, the quiet need within him pushes back with aching severity. Sans lays his hands against the back of Red’s spine and pulls him into the scant remaining space between them. Red’s thigh rests right against the heated tension of Sans’s pubic symphysis, a burning that Sans is certain can be felt through his shorts going by the way Red moans his approval. Sans allows his fingers to slip into the back of the other’s shorts. He tugs once, revealing little more than the fleeting space of smooth bone for the tips of his fingers to rest upon, but he doesn’t pull the shorts down any further, waiting for Red’s consent to continue.

Red doesn’t go far as he leans a fraction away and nuzzles Sans.

“Tempting as it is to just turn you around and bend you over this sink so you could watch in the mirror as I fuck you, a bed would probably be more suited for your ribs,” he says.

He’s got a point. The mental image burns in Sans’s brain, though, and his pubic area pulses with need in response. For a moment, he thinks he’s successfully hidden his arousal at the image Red unfairly shoved into his head. Red then nudges the leg that Sans is damn near straddling, and the grin he flashes him wipes out any remaining bits of dignity Sans might have scraped away. Probably easier if he just pretends he didn’t notice. 

“Yours or mine?” Sans asks.

Red’s smirk says that yes, he definitely caught Sans’s reaction, but he’s also going to be generous and not mention it. How sweet. Sans will be sure to give him a box of his least favorite chocolates as thanks.

“Yours. Boss stills shares a room with me, and I’m not cleaning any mess.” Red inches half a step back so that Sans can appreciate the full force of his grin.

“I also got plans for your mattress. Gonna be smelling me for weeks after today.”

Sans grins back. “You planning on screwing my mattress? Want me to leave you two alone?”

Red hooks a hand into the folds of Sans’s shirt and leads him out of the bathroom as he walks backward. He barely misses clipping his head against the door frame. Red narrows his eyes, daring Sans to laugh. Sans just flashes him an innocent smile.

“Like hell you’re skipping out on the main event,” Red says. “‘Sides, it’s gonna be you that’ll have the pleasure of feeling the mattress springs prodding your back.”

Sans snorts and nearly trips over his feet as Red pulls him a stride faster down the hall towards the bedrooms.

“I wouldn’t hold your hopes too high. There’s always room for a couple coils in your ribs. Who said you’d be up top?”

They step into Sans’s bedroom, and Sans instinctively kicks the door shut behind them. Papyrus and Edge aren’t home and won’t be for several hours, but old habits. 

Sans opens his mouth to declare his victory over Red’s silence, but before he has the chance, Red tightens his grip on Sans’s shirt and hoists him off his feet. In the very next blink, Sans is tossed onto the mattress. The breath is punched out of his chest, and as he’s trying to reclaim it, Red climbs on top of him and plants both hands on the mattress on either side of Sans’s arms. His grin is sharper than ever.

“Call it intuition,” he croons. He ignores the choice names Sans calls him and instead shifts his weight to one hand, using his other to trace a single finger down Sans’s sternum through his shirt. Sans feels his magic flare between his legs, but he doesn’t allow it to take shape. Against all odds, he’s still interested in what Red has planned.

(It’s just been awhile. Give him a break.)

Sans touches the back of Red’s femurs and finds bare bone. Between the time he tossed Sans onto the bed and climbed him like a fucking ladder, Red lost his shorts. The look he’s giving Sans now says he’s intending to do the same to him within the next five seconds. He’d better, or else Sans is going to take matters into his own hands.

Red’s grin is the same, but there’s a light in his eyes that demands Sans’s attention. Red stares hard at him.

“My question is how long has it been since your last lay?”

Sans scoffs. He considers saying something like, “Don’t really see how that’s any of your business,” but that would sound even more telling, and he thinks this is Red’s way of attempting to be a tiny bit less of an asshole. He tries to ignore the finger that is still idly tracing his sternum, intentionally fingering the curve of the scar that would be there. The simple touch unravels Sans, shuddering like he feels it in his soul. It’s such a stupid reaction to something so plain, but even as Red does it again, his breath hitches.

“I have lays. Um, laid. I get laid,” he says, voice totally steady and nonchalant, keeping him coherent and cool.

The silence in which Red stares at him expands. It’s not entirely judgmental. (Ok, maybe a little judgmental, but that’s not something either of them can really ever turn off. But at least Red isn’t being a total dick.)

Red says, “Not asking what your favorite brand of potato chips is, sweetheart, but thanks. I think I got my answer anyway.”

Sans glares. “‘S not my fault. I’m hungry and haven’t eaten breakfast yet.”

“That’s why I’m here.” Red pats him on the cheek with mock affection. “Gonna fill you right up.”

“Wow. Did you rip that from the porno you watched last night? Really not feeling the mood here, bud.”

Before Sans can protest, Red grabs his shorts and yanks them off, tossing them into the corner of the room. Red’s shirt follows and then he’s grabbing Sans by the knees and dragging him over, hooking both legs over his shoulders. He leans forward and damn near bends Sans in half. Sans utters a curse at Red for the unfortunate burst of heat he can feel in his pelvis. Red crooks a brow down at him and then looks pointedly at the magic stirring between Sans’s legs.

“Yeah, it sure looks like it.” Red slips a hand between them and drags a finger through the magic. His other hand slips underneath Sans and gropes his coccyx. A ragged exhale escapes Sans without his permission, but he manages not to completely lose his cool. Red grins at him.

“Why don’t you form something for me, babe, and then we’ll see about getting you in the mood.”

Sans tries to quiet his breathing so as not to seem so affected, and he starts to shift away from the finger tracing along his pubic symphysis. The hand at his tailbone tightens with deliberate intent in an unfairly arousing demonstration of strength. Another burst of heat centers in Sans’s pelvis. He may or may not let out a tiny moan.

Red moves both hands to gripping Sans’s hips, and Sans lets his magic form. It takes the shape of a dick, and Sans blanches. He doesn’t think that’s what Red was hoping he’d form. He looks up at him to gauge any disappointment that might be there. Red stares at his dick with what appears to be no small amount of delight, but Sans has to be sure.

“That ok?” he asks.

Red’s eyelights meet his own again, and very slowly he rests his fingertips at the base of Sans’s dick and drags them up. The touch is maddeningly light, and it feels like every one of Sans’s nerves is centered where Red’s fingers rest. Red greedily watches his expression and grins.

“Yeah, it’s more than all right, babe. Gonna wreck you right through this mattress.”

Red lets Sans’s legs drop on either side of him and he crawls forward to reveal the red magic between his legs that is now a wet cunt. The desire to have Red sit on his face swells within Sans, but he tapers it to weakly laugh instead.

“You’re the one with the cunt, dude. Pretty sure it’s gonna be the other way around.”

Red just smirks at him. His smugness grates against Sans’s rapidly diminishing composure, and Sans can’t help but be into it. Judging by the look on Red’s face, he’s well aware of that, too.

“Nah,” he says unhelpfully. “You made such a pretty cock for me.” A noise escapes Sans even as he’s clenching his teeth to keep quiet. Delight flares in Red’s eyelights.

He continues mercilessly. “Seems only right that I should give it the attention it deserves and ride you until you don’t know which way is up.” Red leans close and nuzzles his cheek, dragging his wide grin down to Sans’s neck where he parts his teeth. Sans’s hands grab hold of Red’s shoulders and tighten, digging his fingertips hard enough into the shoulder blades to hurt. Red groans low, but he doesn’t let up.

“Gonna savor you all damn afternoon, and then I’m gonna use you when you’re all pretty and wet and exhausted.”

He lightly tugs at Sans’s shirt. “Mind taking this off?”

Sans considers for a moment, shrugs, and then does an awkward shimmy of pulling his arms through the sleeves of his t-shirt while Red helpfully continues to sit on him and not move away. The shirt is pulled over his head and then discarded like the rest of their clothing.

Sans’s breath hitches as Red doesn’t wait a second and closes his teeth around his collarbone. He doesn’t bite down hard, though, and Sans firmly stifles any disappointment when Red lets go to drag his tongue against the bone instead. Sans just wishes Red would stop being so damn smug because he can hear his soft snicker.

Red says, voice thick with heavy promise, “Not today, sugar. But maybe later.”

Right. Commitment. Any marks left on Sans might raise a bigger issue after all is said and done. There’s no need for future second guessing. Sans eyes the collar around Red’s throat, remembers how much significance monsters from Red’s universe place on marking and intent. It’s not the same as the familial bond between Edge and Red, but a mark would still be far from trivial.

Sans distracts himself by hooking his fingers around the back of Red’s ribs and pulling. Red curses, but when he follows Sans’s tug and lifts his face, there’s nothing but pleasure written in his expression. He stares down at Sans with ravenous glee.

Sans crooks a brow. “Gonna get on with the show?”

Red snorts. “Gotta get prepped first. That’s show business, baby.”

“Then, you better hurry before the last seat is taken.” He watches Red shimmy down, pushing Sans’s legs out of the way so that his face can sit between them. Sans breathes unsteadily. “There’s a limited number of— Oh, shit.”

Red hums with pleasure, tasting Sans’s dick with aggravatingly slow drags of his tongue. Sans’s hips jerks, and Red pushes him back down until his pelvis is flat against the mattress. Sans’s magic is thrumming, and pleasure radiates down his spine and to his cock. He feels precum wetting the head and spilling down the sides to be thoroughly licked by Red. The groan that falls from Sans’s mouth is loud.

Red lifts his head and wipes at his mouth with the back of his hand. He winks.

“Oh, I’m pretty sure this seat is all mime.”

It takes a moment, but then, Sans chokes out a crazed laugh. “That wasn’t even creative.”

“You love it,” Red says.

Sans is helpless but to grin at the idiot for a second, derailed by the need to get the last word in. He drags a hand down his face.

“Geez, dude. How long is this intermission, anyways?”

Red hums with clear delight. “Glad you admit that the show’s already started. Patience, sweetheart. Isn’t that what you’re supposed to be good at?”

“Fuck you,” Sans says.

“Hold your horses.” Red nips his hipbone, and Sans jolts. His HP doesn’t budge.

To Sans’s great disappointment, Red crawls back up until he’s straddling Sans’s spine, making sure to glide his cunt against Sans’s dick along the way. The warmth of Red’s cunt is heady, and when Red sits back up, looking like the smuggest bastard who knows exactly what he’s about, Sans gets an eyeful of the cunt that’s the same color as Red’s namesake and thoroughly wet. The slightest hint of blue is smeared across the lips of his pussy, turning a near purple, and Sans is rapacious in his stare. He can’t turn away, but he feels Red staring at him and grinning as he slowly reaches a hand down and spreads himself.

“Thought you’d might like some hands on participation,” he says.

Sans hesitates for a fraction of a second and then cups Red’s cunt with his own hand, fingers slipping between the soft folds as he pushes two of them into Red. Sans knocks Red’s hand out of the way and grinds his palm against Red’s clit. Red inhales softly and rolls his hips into Sans’s hand. 

Sans rests his free hand on the inside of one of Red’s thighs and nudges him further open. He thrusts his two fingers into the wet heat at the same time. The moan Red releases is shameless, and Sans feels the echo of its desperation in his own pelvis. His dick is pressed insistently against Red’s coccyx.

“Yeah, that’s the shit,” Red breathes. He begins riding Sans’s fingers in short, jerky moves, a precursor of what’s to come.

Sans smirks up at him. “Like that, do you?”

Red’s laugh is airy and tight. “Y’know it, sweetheart. Don’t worry. I won’t leave you hanging too long.”

“Take your time,” Sans says.

“Heh,” Red says. The grin he shoots Sans doesn’t feel like it should fit when he has Sans’s fingers in his cunt. Or maybe smug is just Red’s constant state of being. “Here.” 

He grabs Sans’s free hand and places it on his sacrum. “Help yourself,” he says with a smirk that rivals Sans’s.

Sans rolls his eyes. He can’t quite appreciate the entirety of Red’s coccyx and finger Red at the same time. It’s been a long time since he’s had practice at ambidexterity in bed. Red grabs the wrist of the hand palming his cunt and thrusts Sans’s fingers into himself even harder. His grin is terrifyingly beautiful.

“Just focus on the one,” he croons. “C’mon, I know you can do it.” He lifts himself off of Sans and drops back down again. Sans can’t help the moan that leaves him, and Red doesn’t give him a break, continuing to ride him in short, slow motions. He’s taking his sweet ass time, and Sans hates every moment of it. He pinches the holes of Red’s sacrum in retaliation. 

“Oh, fuck. That’s it, sweetheart, yeah,” Red moans. His grip remains iron-tight around the wrist he’s damn near controlling. “You’re doing so well. So good.”

The blush scalds Sans’s face.

“You love to hear yourself in bed, huh?” he says.

Red breathes a laugh. “Not just in bed, honey. I ain’t got limits.”

Sans can feel the way Red’s pussy is clenching around his fingers, and when Red thrusts down again, he curls them to rub brutally against Red’s walls, searching for the spot that will make Red moan. Red grins at him, and he stops thrusting to roll his hips instead, and as Sans curls his fingers again, Red closes his eyes and releases a low, satisfied growl.

He begins to ride Sans’s fingers like he’s in heat, and the way slickness runs down Sans’s hand makes his dick throb. But Sans wants to see Red come first. The way he uses Sans to get off is doing things to Sans’s untouched dick. He decides to try and get a modicum of control back, and with one final rub of Red’s sacral foramen, he lets go and braces his hand on Red’s thigh.

Red opens his eyes again, heavy-lidded. 

“Gettin’ impatient, sweetheart?”

“Nope,” Sans says without a single tremble in his voice. “Take your time. You look like you’re having fun.”

“Aww, if you were feeling lonely, you should’ve said something. I’m more than happy to provide.” 

Sans tries to thrust his fingers hard into Red when he’s thrusting down, but the grip around his wrist is firm. There’s likely going to be a bruise, and at that thought, he feels more wetness spill from the head of his dick. His body is a traitor that needs to shut up because there’s no way he’d find pleasure in pain.

Ignoring his internal dilemma for the moment, Sans watches Red slip off his fingers with a sigh. It’s sad that Sans didn’t get to see him come undone yet, but that’s surely something Red won’t deprive him of for long. For now, Red gentles his hold on Sans’s wrist. Keeping his gaze locked with Sans’s, he smoothes a thumb tenderly over the sore wrist. The spike of heat and want is dizzying.

Sans tamps down on the groan before it can escape. He’s breathing loudly through his clenched teeth, which is stupid because Red hasn’t done anything to him yet. He shouldn’t feel this fucked up over absolutely nothing.

He slides a shaky grin Red’s way. “Gonna move on to the main event?”

Red’s stare is avid and bright. He quirks a grin of his own. “Yeah, sweetheart. Let’s see how messed up I can’t get you.”

With one last gentle rub of Sans’s wrist, he lets go and knee-walks back. He takes Sans’s dick in hand and adopts a gleeful grin.

“‘Scuse me, sir,” Red says in a sudden, horrible imitation of a cockney accent, “Is this seat taken?”

Sans’s laugh is choked out of him, but it quickly turns into a ragged moan when Red’s pussy takes all of him at once in a single thrust. The wet heat of Red’s walls clutches the whole of Sans, and his chest feels tight in desperation for air he doesn’t need. 

His fingers scrabble for purchase, trying to find some reorienting stability as he grips Red’s ribs tightly. He slides one hand down and wraps it around the scarred mess of Red’s spine. Red’s groan ratchets up in volume the tighter Sans squeezes, and the noise only adds to his throbbing magic.

Red begins to ride him slow, so very slow, like he’s savoring the feeling of Sans within him. He clenches tight on every downward thrust. Sans refuses to be outdone by the torturous pace Red has set, and he uses his hold on him to pull Red down at the same time that he thrusts his pelvis up. 

“Fuck,” Red moans shamelessly. “Oh, fuck, sweetheart, yes.”

With the next few thrusts, he allows Sans to use him freely for his pleasure, the slow pace turning frantic as Red lets Sans do the work of moving him up and down on his dick. At some point, Red stops using his thighs to lift himself up, and he becomes like deadweight as Sans takes over. Moving Red’s full weight as he just sits there and has Sans do the work for him quickly becomes too great of a task for Sans’s arms, and after a few more heavy thrusts of his pelvis, Sans relaxes his grip on Red. He can feel sweat running down the sides of his skull, his chest heaving with effort, and his soul feeling like it could flee from his chest with every pounding beat. He’s exhausted, and it’s becoming rather clear that he doesn’t have the energy or stamina to use Red however he wishes. Too much inactivity has left him useless. Judging by the grin Red is giving him, he knows it too.

Red leans forward, bracing his hands on Sans’s chest and fanning out his fingers. His expression is tight and blissful at the new angle as he sighs contentedly. He looks like the cat that got the cream, and Sans is unable to look away.

“There,” Red says sweetly as he grins at Sans. “Got it out of your system? Good. Now, just let me fuck you up, sweetheart.”

He resumes the same tortuously slow pace from before, allowing Sans to feel every inch of his wet cunt drag against his dick.

Sans shudders out a breath. He opens his mouth to complain, but there’s really nothing to complain about. Red is using him carefully, thoroughly, treating him like something precious that’s meant to be handled with the greatest attention. Sans can’t stop the moan this time when Red deliberately tightens around him. He turns his head away from Red’s gaze that pierces his soul. It’s like Red is taking him apart one piece at a time with every gentle thrust on his cock, and it’s making the heat across Sans’s face burn hot.

His fingers find Red’s sternum, but he doesn’t press against the would be scar. Instead, he matches Red’s unbearably slow and sweet pace, lightly petting the not-scar with his thumb. The shudder wracks through Red’s entire body as if that single touch unmade him, but he doesn’t let up. He laughs hoarsely, and his cunt squeezes Sans impossibly tight.

“Hnn,” Sans says, the noise pulled from behind his teeth. He clenches his eyes shut and tries to focus on matching Red’s pace with slow thrusts of his own. 

Red’s tongue finds his sternum and then he scrapes his teeth around the middle like a warning. After a careful moment of waiting for any protest and finding none, Red bites down just enough to sting, but not enough to leave a mark. It doesn’t matter. The sensitivity of Sans’s sternum causes his magic to flare in response, and Red groans. He sits up, keeping his hands planted on Sans’s ribs, and the pressure against his chest pushes Sans into the mattress just as strong as gravity magic. He opens his eyes to see the concentrated furrow in Red’s brow. Red must see something in his expression because he breathes raggedly and without warning drops down on Sans’s dick and begins to ride him faster, jerkier thrusts. The back of Sans’s head thumps against the mattress as his mouth drops open, but no sound escapes.

“Fuck, look at you. You’re all fucked up. You’d take just about anything I’d give you,” Red gasps, and Sans huffs out a shaky breath in response. He’s close, can feel the familiar spiral of heat tightening with every thrust, and he’s helpless to do more than hold on as Red uses him. He’s along for the ride as Red chases his pleasure, and as Red clenches around his dick, Sans can feel himself rapidly approaching the edge that Red will inevitably push him off. His breathing echoes in the room, and he can’t stop it. The promise of pleasure burns in the wet heat of Red’s pussy and the demanding look in his eyes that redraws Sans’s attention.

“That’s right, sweetheart. So good for me, so perfect. C’mon, just let it happen, just let me fuck you up. That’s it, that’s— Oh, fuck!”

Red’s fingers tighten around his ribs as his the heat of his pussy sharpens to severity in orgasm, and Sans is dragged down with him. He feels the breath punched out of his chest as he cums, the tight heat surrounding every inch of him and flooding him with pleasure. His head tips back, and his heels press into the mattress, and nothing matters but the bright point of release that leaves him shaky in the aftermath, his bones rattling with the force of it.

The fluttering pulses in the wake of Red’s orgasm presses against his overstimulated dick, and he flinches. Red’s pleased sighs do nothing to help Sans’s situation, but he takes it. Just like how he took everything else Red gave him. Fuck, he’s fucked up. He can’t help the twitches his hips make with every spasm of Red’s cunt, and the slight pain brings another sympathetic burst of wetness. Red groans full-throatedly.

For a minute, Sans just tries to remember how to breathe. His head is dizzy with the heat, and he closes his eyes to keep the room from spinning in turn.

He feels Red stretch against him like a cat, humming with unfair contentedness like he wasn’t the one who just got fucked. Together, they lie there and breathe. Sans struggles to catch his breath with Red draped on top of him, but the weight is a compensating comfort in which he basks. For a moment, there’s nothing on his mind but the distant ache in his magic and Red. 

With a final, satisfied groan, Red pulls himself off of Sans’s dick. Instead of slipping to the side of Sans, he shifts down his body and doesn’t give him a moment to think before his face is between Sans’s legs, and his hands are wrapped around his thighs. In one breath and the next, Red’s mouth is on him, and without warning, he takes all of Sans.

The tension in Sans’s shoulders dives back in with the feeling of his dick pressing against the back of Red’s throat, the wet drag of Red’s tongue like the best pleasure even as his dick aches from all of it. It’s too much. Red doesn’t let up, moaning thickly, and Sans claws at his sheets as his spine curves. It’s exquisite agony, painful and delicious in every way, and he can feel his release building again with frightening speed as Red swallows around him again and again. Sans is overheated, his head light as every single ounce of feeling is concentrated in his dick. Red’s throat works him, taking him impossibly deep and so, so good, and within a few minutes of Red deepthroating him, moaning with pleasure around his dick, Sans comes with a wrecked cry. He feels Red swallow it all and give another throaty groan that forces Sans to unconsciously pull away.

His face twists with the feeling, and to his relief, Red releases him with a wet noise. Sans is shuddering uncontrollably, the aftershocks incapable of being hidden, and he feels like he could do little more than bend a finger.

It’s stupid that Sans is this messed up from two orgasms, and even as his joints still thrum with heated magic and his chest keeps pounding, something like unease begins to creep in. 

What will Red think of him now? Sans has been messed up by simply being ridden into the mattress and having the fastest, best damn blowjob of his life, and he doesn’t think he has the energy to go again if Red wants to. Fuck kind of lay is he to already be this unmade. He didn’t used to be this passive in bed. Red is going to realize how boring Sans is, and the risk of disappointing him stirs in his soul like nausea.

Red crawls back up and presses his head against Sans’s neck, inhaling long and slow. His grin is sharp against Sans’s bones.

“Fuck, sweetheart, you keep dishing out the surprises, don’t you?” 

His voice is fucked out, hoarse in a way that is evident in no uncertain terms that he just sucked Sans’s dick, but Sans can only focus on his words. The feeling in his soul spikes with accumulating worry. Red rolls to the side of Sans and tugs an arm around him.

“C’mere.” He pulls Sans to his chest, and as they rest and Sans regains his breath, some loud part of his mind slowly turns quiet. 

“Where the fuck you’ve been hiding all my life?” Red says. “You were so good for me, so willing.”

In Red’s embrace like this, Sans can’t hide his shudder. Relief flows with Red’s approval, and Sans groans.

He finally manages to utter, “Gimme a few hours, and I’ll return the favor.”

Red snickers. “I’ll hold you to that, honey,” he says. He sounds like he’s looking forward to it.

Sans stretches out the soreness in his bones, but he doesn’t attempt to roll out of Red’s arms. He purposely ignores any connotations that follow that thought. He’s earned this. Let him linger. His brain can have a freakout later after he’s cooled down.

He sighs against Red’s chest. “Just so y’know,” he says with utmost conviction, “I’m not into any kinky stuff if you decide to make things more adventurous.”

There. Casually letting Red know that he’s willing to have a repeat session. Let him decide what to do with that.

Red hums as his hand reaches between them and finds the wrist that he left a bruise on. It’s tender to the touch, and Sans snaps it out of his grip. He can nearly taste the grin on Red’s stupid face.

“No jungle gym, then? Shame. Guess I’ll have to get used to the taste of vanilla. I’ll miss my chocolate ice cream.”

“Chocolate is overrated,” Sans says into Red’s chest. 

“Mm, but there’s always room for compromise. Ever had a chocolate and vanilla swirl? It sits on the tongue juuust right.”

Sans snorts. It’s just Red’s usual bullshit. He feels the relief soothe the last of the remaining tension. Sans pushes away a little so he can lift his head and give Red the look that that statement deserves. 

“Yeah, right,” he says. “Admit it. You robbed the ice cream truck of every single bar of chocolate sundae crunch.”

Red waggles his brows. “Actually, I fucked the driver against the hood of the ice cream truck first, and then I raided his stash of cream.”

Sans lifts a hand and rubs at his eyes. 

“Can you not say it like that.”

“Say please, and I’ll do anything you want,” Red says.

Sans is too tired to form his magic again, dissipated in the aftermath of Red’s surprise blowjob, but he feels it flicker in appreciation. He drops his hand in time to see Red’s promising smirk, and it doesn’t help that he’s going to think of this afternoon every time he sees that look on Red’s face now. His dick is stupid and needs to stop weighing in on everything. Especially when Red is looking at him like that.

Red leans forward and kisses him. It’s not heated or rushed, just slow and purposeful like the rest of the afternoon has been. Sans leans into the kiss and tastes himself on Red’s tongue. 

After a long few moments, Sans pulls back. His face feels flushed, which is ridiculous considering that they just fucked. The headiness of Red’s gaze invites him to spend an entire day making out with him in bed. With a grunt, Sans flips onto his back. He’ll worry about things like his and Red’s relationship later. 

(Fuck, not a relationship. It’s nothing like that. More like fuckbuddyship, if even that.)

Red doesn’t seem to pick up on Sans’s thoughts, or if he does, he doesn’t bother saying anything. They’ll figure things out later. Instead, Sans focuses on Red’s hand as it idly plays with Sans’s ribs, fingers tracing them to where they connect with his sternum, which is still oversensitive from where Red bit down. Sans swats at Red to which he receives an encouraging growl that doesn’t help his situation. He sighs.

“So,” Red says, his grin distinct in the sly pull of his voice, “About that second shower...”

Sans laughs.

**Author's Note:**

> Content warning: mentions of Sans prostituting himself in the past to get just barely enough money to survive
> 
> <strike>;.; lyra's first smut, please be gentle</strike>
> 
> Thanks for reading!


End file.
